28 NOTES
Advanced Platform Development
Rebuilding a complete self-hosted data platform from FOSS on Kubernetes, one working component at a time.
→ Start herePlexara: A Managed MCP Layer for Data Platforms
Deasil operates the endpoint. The engine is txn2/mcp-data-platform, Apache-2.0. I wrote the harness this replaced.
→ Read this noteLatest note · folio diagram
flowchart LR C["Claude"] --> P G["ChatGPT"] --> P A["Custom agent"] --> P P["Plexara<br/>one MCP endpoint<br/><i>txn2/mcp-data-platform</i>"] P --> IDP["Customer IdP<br/>Keycloak, Okta, Entra"] P --> DH["DataHub<br/>catalog, lineage, glossary"] P --> TR["Trino<br/>federated SQL"] P --> S3["S3<br/>object storage"] P --> PG["PostgreSQL<br/>memory, knowledge, audit, assets"] P --> API["Vendor APIs<br/>ERP, POS, ticketing, CRM"] P --> MCP["Other MCP servers"]
I have been assembling data platforms for clients for over twenty years. For most of 2025 I was also writing the glue that let a language model sit on top of them. Plexara is what Deasil Works runs in place of that glue: …
Current Series
20 NOTES
MCP Without the SDK
The Model Context Protocol taken apart one JSON message at a time, written by hand in Go.
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5 NOTES
MCP Studies
Measured studies of MCP agent behavior: knowledge-layer ablation, stored-knowledge use, the measurement harness, knowledge pollution, and cross-reference document completion.
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5 NOTES
AI on a Leash
Mechanical verification for AI-written code: strict linting, coverage gates, mutation testing, and a pre-commit gate that refuses the commit.
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Recent Notes
150
Don't Impersonate the Caller. Put the Credential on the Connection.
Trino, S3, DataHub, and vendor APIs do not share an identity model. They all have a credential.
2026-09-03
149OAuth in Front of Keycloak
Pre-registered clients and PKCE. Login stays in the IdP.
2026-09-01
148REST APIs for Agents
Index the OpenAPI document. Search across catalogs. Then call one operation.
2026-08-30
147Sessions Left the Protocol. Put the Handle in the Argument.
platform_info mints dps_…; the model threads it. Go SDK v1.7.0, MCP 2026-07-28.
2026-08-28
146Don't Ingest the CSV. Point Hive at It.
Hive still maps a table name to a directory of files
2026-08-26
145Don't Sandbox Python. Embed Starlark.
starlark-go in a Go server: FileOptions, host bindings, and a cancel watchdog
2026-08-24
144God Packages and Other Slow Failures
Structural ratchets for AI-assisted Go, six months into make verify
2026-08-22
143Do Cross-References Help LLM Agents Complete Documents?
The agent found every page certified unreachable. Links cut search cost and keep working when search is off; they do not change what it reaches
2026-08-20